Purpose: To study the characteristics of the accompanying amblyopia and strabismus in patients with anisometropia. Methods: We retrospectively reviewed the medical records of 193 patients, who had either spherical or cylindrical anisometropia of more than 1.00D. Patients were divided into four groups: spherical hyperopic anisometropia, spherical myopic anisometropia, cylindrical hyperopic anisometropia, and cylindrical myopic anisometropia. We investigated the accompanying amblyopia and strabismus. Amblyopia was treated with lens correction and patch therapy and we analyzed the results for 78 patients who fulfilled six-month follow-up examinations. Results: There was no significant difference in the frequency of amblyopia between spherical and cylindrical anisometropia. Spherical myopic anisometropia of more than 3.00D showed a significant increase in the incidence of amblyopia (p=0.001). Spherical hyperopic anisometropia of more than 1.00D, cylindrical hyperopic anisometropia of more than 2.00D, and cylindrical myopic anisometropia of more than 2.00D showed an increased tendency for amblyopia. Between spherical and cylindrical anisometropia, there were no significant differences in the results and duration of amblyopia treatment, and type and frequency of strabismus. Conclusions: In spherical anisometropia, hyperopic anisometropia has a higher risk for developing amblyopia. We could find the threshold for the development of amblyopia.